Disk drive manufacturers typically test manufactured disk drives for compliance with a collection of requirements. Test equipment and techniques exist for testing large numbers of disk drives serially or in parallel. Manufacturers tend to test large numbers of disk drives simultaneously in batches. Disk drive testing systems typically include one or more racks having multiple test slots that receive disk drives for testing.
The testing environment immediately around the disk drive is closely regulated. Minimum temperature fluctuations in the testing environment are critical for accurate test conditions and for safety of the disk drives. The latest generations of disk drives, which have higher capacities, faster rotational speeds and smaller head clearance, are more sensitive to vibration. Excess vibration can affect the reliability of test results and the integrity of electrical connections. Under test conditions, the drives themselves can propagate vibrations through supporting structures or fixtures to adjacent units. This vibration “cross-talking,” together with external sources of vibration, contributes to bump errors, head slap and non-repetitive run-out (NRRO), which may result in lower test yields and increased manufacturing costs.
During the manufacture of disk drives or other storage devices, it is common to control the temperature of the storage devices, e.g., to ensure that the storage devices are functional over a predetermined temperature range. For this reason, the testing environment immediately around the storage devices is closely regulated. Minimum temperature fluctuations in the testing environment can be critical for accurate test conditions and for safety of the storage devices. In some known testing systems, the temperature of plural disk drive devices is adjusted by using cooling or heating air which is common to all of the disk drive devices.